4-alkylamino-3-nitroquinolines

ABSTRACT

The herbicidal compounds have the formula:   WHEREIN: R1 and R2 are each hydrogen, lower alkyl, or (lower alkylthio)lower alkyl except that R1 and R2 may not both be hydrogen, X is hydrogen, halo, or trifluoromethyl.

United States Patent Diehl et al.

[54] 4-ALKY LAMINO-B-NiTROQUINOLINES [73] Assignee: American Cyanamid Company,

Stamford, Conn.

[22] Filed: April 30, I969 [21] Appl. No.: 820,649

[52] US. Cl ..260/288 R, 71/94, 2,60/283 S, 260/283 SY, 260/283 R [51] Int. Cl. ..C07d 33/52 [58] Field of Search ..260/288 [5 6] References Cited UNITED STATES PATENTS 2,066,730 1/1937 Jensch ..260/288 X 3,113,072 12/1963 Goodhue et al. ..260/288 X 3,252,858 5/1966 Goodhue ..260/283 X 2,661,276 12/ 1953 Schlesinger ..260/283 X 2,665,203 1/ 1954 Emerson ..260/283 X 3,470,172 9/1969 Kaufman ..260/295 X [451' Oct. 24, 1972 OTHER PUBLICATIONS Surrey et al., Jour. Am. Chem. Soc. Vol. 73, p 2413- 2416 1951) Jain et al. Chem. Abstr. Vol. 68 Col. 1 l4396t (1968) Primary Examiner-Donald G, Daus Attorney-Lawrence W. Flynn 57 ABSTRACT The herbicidal compounds have the formula:

wherein:

R, and R are each hydrogen, lower alkyl, or (lower alkylthio)lower alkyl except that R and R may not both be hydrogen,

X is hydrogen, halo, or trifluoromethyl.

5 Claims, No Drawings 1 4-ALKYLAMINO-3-NITROQUINOLINES SUMMARY OF THE INVENTION This invention relates to novel herbicidal 4-alkylamino-3-nitroquinolines represented by the formula:

R and R are each selected from the group consisting of hydrogen, lower alkyl, and (lower alkylthio)lower alkyl provided that when either R or R is hydrogen, the other must be lower alkyl or (lower alkylthio) lower alkyl,

X is selected from the group consisting of hydrogen halo, and trifluoromethyl.

This invention also relates to the acid salts of sai compounds and in particular to the strong mineral acid salts thereof such as, for example, those of hydrochloric and hydrobromic acid.

This invention further relates to the use of said compounds and their acid salts as pre-emergence and post emergence herbicides.

The term lower alkyl when used alone means.

straight and branched saturated hydrocarbon chains containing from one to five carbon atoms. Illustrative members are methyl, ethyl, n-propyl, n-pentyl, n-butyl, isopropyl, 2-butyl, 3-butyl, 2-pentyl, 3-pentyl, and such.

The term lower alkyl when used in conjunction with thio radicals such as (lower alkylthio)lower alkyl radicals means only saturated hydrocarbon chains containing one or two carbon atoms such as methylthio) methyl, (methylthio) ethyl, (ethylthio) methyl, and (ethylthio) ethyl.

The term halo means chloro, bromo, iodo, and fluoro.

The following compounds are illustrative of the com pounds of this invention. These compounds are named in accordance with the numbering of the quinoline ring given in the preceding formula:

4-methylamino-3-nitroquinoline 3-ethylamino-3-nitroquinoline 4-n-propylarnino-3-nitroquinoline 4-n-butylamino-3-nitroquinoline 4-n-pentylamino-3-nitroquinoline 4-( i-propyl )amino-3-nitroquinoline 4-( 2-butyl )amino-3-nitroquinoline 4-dimethylamino-3-nitroquinoline 4-diethylamino-3-nitroquinoline 4-dipropylamino-B-nitroquinoline 4-di( i-propyl )amino-3-nitroquinoline 4-di(n-butyl)amino-3nitroquinoline 4-di( n-pentyl )amino-3-nitroquinoline 4-di( Z-butyl )amino-S-nitroquinoline 4-methyl( ethyl )amino-3-nitroquinoline 4-methyl( n-propyl )amino-3-nitroquinoline 4-ethyl(n-butyl )amino-3-nitroquinoline 4-n-butyl( i-propyl )amino-3-nitroquinoline 4-n-pentyl( 2-butyl )amino-3-nitroquinoline 4-n-propyl( ethyl )amino-3-nitroquinoline 6,7,8-trifluoro-4-methylamino-3-nitroquinoline 6,7,8-trichloro-4-n-propylamino-3-nitroquinoline 6,7 ,8-tri( trifluoromethyl )-4-n-butylamino-3- nitroquinoline 6,7,8-triiodo-4-n-pentylamino-3-nitroquinoline 5',6,7-trichloro+4-(i-propyl)aminoJ-nitroquinoline 5 ,6,7-tribromo-4-( 2-butyl )amino--3-nitroquinoline 5 ,7,8-trichloroF4-dimethylamino3 nitroquinoline 5 ,7 ,8-tribromo-4-dimethylamino-3-nitroquinoline 8-chloro-7-bromo-6-fluoro-4-dipropylamino-3 nitroquinoline ,78-dichloro-6-iodo-4-di(i-propyl)amino-3- nitroquinoline 6,7-dibrorno8-chloro-4-di( n-butyl )amino-3- nitroquinoline 5 ,6-'dichloro-7-bromo-4-di( n-pentyl )amino-3- nitroquinoline 5,8-dichloro-4-di( 2-butyl )amino-3-nitroquinoline 6,7-.dichloro-4-methyl( ethyl )amino-S-nitroquinoline 5,6-dichloro-4-methyl(n-propyl )amino-3-nitroquinoline 7,8-dibromo-4-ethyl( n-butyl )amino-3-nitroquinoline 5 ,6-diiodo-4-n-butyl( i.-propyl )amino-3'-nitroquinoline 6,7-difluoro-4-n-pentyl( 2-butyl )amino-3-nitroquinoline 8-chloro-4-n-propyl( ethyl )amino-3-nitroquinoline 7-trifluoromethyl-4-methylamino-3 -nitroquinolin e 6-iodo-4-n-propylamino-3-nitroquinoline 5-fluoro-4-n-butylamino-3-nitroquinoline 6-chloro-4-n-pentylamino-3-nitroquinoline 8-nitro-4-( i-propyl )amino-3-nitroquinoline 7-nitro-4-( Z- butyl )amino-3-nitroquinoline 6-nitro-4-dimethylamino-3-nitroq uinoline 5-nitro-4-diethylamino-3-nitroquinoline 8-trifluoromethyl-7-chloro-4-dipropylamino-3- nitroquinoline 8-bromo-6-nitro-4-di( i-propyl )amino-3-nitroquinoline 7,8-dichloro-5-nitro-4-di( n-pentyl )amino-3- nitroquinoline .6,7-dinitro-8-chloro-4-methyl(ethyl )amino-3- nitroquinoline 6,7,8-trinitro-4-ethyl( n-butyl )amino-3-nitroquinoline 5,6,7-trinitro-4-n butyl(i-propyl )amino-3-nitroquinoline 6,7-dinitro-4-n-pentyl( 2 butyl )amino-3-nitroquinoline 5 ,6.-dinitro-4-n-propyl( ethyl )amino3- nitroquinoline PROCESS OF PREPARATION nNR Rn wherein R R X, and n are as previously defined.

The reaction is preferably run at solvent reflux te mperatures which-ordinarily rangevfrom 120 C. atv

atmospheric pressure. Suitable solvents includev aromatics such as toluene, and benzene, chlorinated hydrocarbons such as chloroform, carbon tetrachloride, dipolar aprotic solvents such as dimethylsulfoxide and dimethylformamide, and such. It is desirable to use an excess of the amine, usually at least about 2 moles of amine per mole of 3-nitroquinoline compound. The excess amine forms an acid salt which precipitates from the reaction mixture thereby aiding purification of the desired product. After the precipitated acid salts are separated from the reaction mixture, solvent is removed to yield a crude product which can be subsequently purified by recrystallization in acetone or other suitable solvents. Of course, it the acid salt of an inventive compound is desired, it is a simple matter to merely react the product with the desired acid in a manner which is well known.

STARTING MATERIALS The vast majority of the reactant amines are readily available on a commercial basis. Techniques for preparing the other amines required are either well known or obvious to those skilled in the art so as to not require repeating herein.

Reactant 4-chloro-3-nitroquinolines of the formula:

XII

where X and n are as defined above, in accordance with the teaching in J .A.C.S. 69 page 371 said publication incorporated herein by reference. The decarboxylated product is then nitrated in a conventional manner to insert a nitro group into the number 3 position of the quinoline ring. The nitrated quinoline is then treated in accordance with the process of Bachman et al., cited above, to yield the desired 3-nitro-4-chloroquinoline reactant.

The desired reactant can also be prepared by reacting ethyl oxalacetate and an aromatic amine as described in US Pat. No. 2,555,943 to obtain a 2-carboethoxy derivative of the formula:

UTILITY The compounds of this inventionexhibit preem ergence herbicidal activity towards a variety of broad'and narrow leaf plant species. Pre-emergence control is particularly effective as amply demonstrated by the data of Example 14 hereinbe low. It should be noted that ,the pre-emergence herbicidal activity of these compounds is highly selective insofar as they are efiective against a broad range of undesirable weeds which grow among crops while simultaneously having no discernible herbicidal effect upon such useful economic crops as corn, cotton, radish, sugar beets, soybeans, and wheat.

Certain selected compounds of this invention exhibit post emergence herbicidal activity towards a variety of broad and narrow leaf plant species as amply demonstrated by the data of Example 15. While all of the inventive compounds exhibit pre-emergence herbicidal activity, only those compounds where n is zero and R and R are each lower alkyl or (lower alkylthio) lower highly selective in that crops such as tomatoes and wheat are left virtuallyunharmed while the harmful weeds and grasses which grow among such crops are effectively destroyed.

Application of the compounds of the invention for purposes of herbicidal control can be accomplished employing both conventional type formulation and equipment. The compounds may, for instance, be formulated as wettable powders, dusts, dust concentrates, emulsifiable concentrates and the like which are amenable to application with conventional spraying or dusting apparatus.

Wettable powder formulations are generally preparedby admixing from about 25 percent to about percent, by weight, of active ingredient with finely ground clay, such as kaolin or attapulgite, either with or without a surface active agent, emulsifier or spreader-sticker. The latter is then dispersed in water for spray application.

Dusts and dust concentrates are similarly prepared using from about 5 percent to about 95 percent of active ingredient and from about 95 percent to about 5 percent of finely divided inert ingredients. These dusts are generally applied as such, or they may be further diluted with finely ground inert solids and then applied with conventional dusting apparatus.

Emulsifiable concentrates may be prepared by dissolving ordispersing the active ingredient in organic solvent, with or without emulsifying agents, surfactants or the like. Such formulations are then diluted with either water or an appropriate .organic diluent prior to application.

The following examples are provided to further illustrate the invention.

EXAMPLE 1 Preparation of 4-di-n-propylamino-3-nitroquinoline The title compound is prepared by refluxing a sample of 4-chloro-3-nitroquinoline (4.16 g., 0.02 mole) and di-n-propylamine (4.05 g., 0.04 mole) in 40 ml. of toluene for 2 hours. The mixture is then filtered to remove the insoluble hydrochloride salts. The filtrate is concentrated, in vacuo, to yield 4.5 g. (83 percent) of a dark brown oil which gradually crystallizes. After three recrystallizations from acetone, the yellow-orange solid has a melting point of 63 -64 CLCaiculated for C, .,H ,N3O C, 65.90; H, 7.00; N, 15.37. Found: C,

mixture is heated for 2 to 4 hours at 80-90 C. and poured into 500 ml. of ice-water. The precipitated solid is filtered and washed well with water. The sample is recrystallized from dimethylformamide-water to give 5,8-dichloro-3,6-dinitro-4-hydroxyquinoline. The product is then converted to 4,5,8-trichloro-3,6-'

dinitroquinoline following the method of Bachman et y al. J .A.C.S. 69, pages 365-370 1947).

The desired product, 5.8-dichloro-3,6-dinitro-4-di-npropylaminoquinoline, is then prepared following substantially the same procedure as'in Example 1 except that the 4-chloro3-nitroquinoline is replacedby 4,5,8-

trichloro-3,6-dinitroquinoline.

EXAMPLE 13 Preparation of 5,8-dibromo-3,6-dinitro-4-di-ny propylaminoqumolme EXAMPLES 2 TO 1 1 I mcanrnh A variety of other inventive compounds were prepared substantially as described in Example 1 ex- (ml-p cept that the appropriate 4.-chloro-3-nitroquinoline and amine reactants were selected. These compounds and N/ certain of their properties are shown below in Table l. M

TABLE 1 W -Nm I 4 "N0: i x" I imam" x*- 8 I/ I i 8 l \/\N V N Melting Exam le 0 n numb r Bl R; R, xc.) c 11 N s 01 F 2 H cHwHm H ,H c 65.90 7.00 15.37

98 I 00.12 0.03 15.09 3 CzHs 1 4110 H H 7243 g 4 n-ctm IICSHI H 01(0) M {f 1& 1 I 1 i a 003111 31-03111 H 01(1) {g (gig g1 33 1 6 'C3H7 'CH .11 01(8) 105-106 gfig 7 02H: l l H (7) 63454 s I1-CaH1 11-03111 H moo) 94% gig gig gig; 1' u n-otm 11-08111 H 110(8) H18 {f 1 g gig; gig? 1o 11-0011 11-03111 H N02(fl) 101402 {f gig: Z2: gig 11 11-03111 CH2CH2S.CH: H H 694 {f 59 gig 1 $3 I Number in parenthesis indicates ring position. b c=calculated; t=lound.

5.0 Grams of 5,8-dichloro-4-hydroxyquinoline [Prepared according to US. Pat. No. 2,555,943 (C.A. 45, 9568)] is added to a solution of nitric acid ml.) and sulfuric acid (50 ml.) a t g ll'ite resulting The above compound is prepared following substantially the same procedure as in Example 12 except that 5,8-dichloro-4-hydroxyquinoline is replaced by 5,8- dibromo-4-hydroxyquinoline.

EXAMPLE 1'4 Pre-Emergence Herbicial Test The pre-emergence herbicidal activity of the compounds of the invention is exemplified by the following tests in which the seeds of various monocotyledonous and dicotylendonous plants are separately mixed with potting soil and planted on top of approximately 1 inch of potting soil in separate pint cups.After planting, the

cups are sprayed with the selected aqueous acetone.

solution containing the test compound in HERBITOXICITY INDEX 9 100 percent reduction in stand 9"= l or 2 stunted plants remaining 8 85 100 percent reduction in stand 7 70 85 percent reduction in stand 6= 60 70 percent reduction in stand 50 60 percent reduction in stand 4 40 50 percent reduction instand 3 30 40 percent reduction in stand 2 20 30 percent reduction in stand 1 10 20 percent reduction in stand 0= no apparent efiect a abnormal, malformed, twisted g= unusual physiological effect m moderate injury s severe injury t= trace to slight injury no test Abbreviations for the plant species employed in Examples 14 and 15 are as follows:

Bu 8 Barnyard Grass Mu I Mustard Cor Corn Pi Pigweed Cot Cotton Ra I Radish Cr Crabgrass SB 8 Sugar beets GRF Green Foxtail Soy Soybeans Ln Lambsquarters To Tomatoes Mi 8 Millet W0 Wild Oats wan-swa er,

a. It:

NO: (X)n EXAMPLE 1 5 Post Emergence Herbicidal Test The post emergence herbicidal activity of the compounds of the instant invention is demonstrated by treating various monocotyledonous and dicotyledonous plants with the compounds dispersed in aqueous-acetone mixtures. In the test, seedling plants are grown in jiffy flats for about2 weeks. The test compounds are dispersed in 50/50 acetone/water mixtures in sufficient quantity to produce concentration of the desired pounds per acre of active compound when applied to the plants through a spray nozzle operating at 30 psi. for a predetermined time. After spraying, the plants are placed on greenhouse benches and are cared for in the usual manner, commensurate with convention greenhouse practices. Two weeks are treatment, the seedling plants are examined and rated according to the Herbitoxicity lndex provided in Example 14.

,8 Results are in Table III below.

TABLE III. ros'rr-Msaosnca l-IERBICIDAL DATA Compound Ib./

of Ex. No. acreLa, Mu Pi Ba Cr GRF TO WH .l v 10 .9 ma 9 m 80 m a se 0 3 1o 9 9- 9 a 7 3 m o lclairn:

.1. A 4-alkylamino-3-nitroquinoline compound 1.5 represented by-the formula:v

- Thelcompound according to claim 2:

moan-n,

4. The compound according to claim 2: I

.5. The compound according to claim 2:

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5 7 7 med October 2 1972 Inventor(s) Robert E. Diehl and Richard J. Magee It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below: Column 7; above the words "Example 15" delete the formula and replace with Table II shown below:

TABLE II. PRE-EMERGENCE HERBICIDAL DATA Compound of Example Number Lb./Acre Pi Ba Cr GRF N0 M1 Cor Cot R a SB S01 E 5 73a 8a 9a 9a ta 1 9 9a 9 9a 6a 5 9 o 3 tga 7 3a 7 O O O O O 3 9 eggs 05 Ba 9 o o o o o 5 5s; a 9 9a 0 h 5s 95 9 9 o 9a o o 5 5 g gss 'v's H 9a o o i 6 22 52 29955 6 6 7 p; 9 3 2 995; 2959.;

Signed and sealed this 13th day of March 1973.

(SEAL) Attest;

EDWARD M.FLETCHBR.JR. ROBERT GOTTSCHALK Attestlng Officer Commissioner of Patents F ORM PO-IOSD (10-69) USCOMM-DC 6Q376-P69 5. GOVIIIIIIENT IRINTIIG OFFICE: l9! 0-36-334 

2. A compound of claim 1 wherein R1 and R2 are each lower alkyl.
 3. The compound according to claim 2:
 4. The compound according to claim 2:
 5. The compound according to claim 2: 